# -*- coding: utf-8 -*-

# This code is part of Amoco
# Copyright (C) 2014 Axel Tillequin (bdcht3@gmail.com)
# published under GPLv2 license

from amoco.system.core import *
from amoco.code import tag

import amoco.arch.pic.cpu_pic18f46k22 as cpu


class PIC18(object):
    def __init__(self, p):
        self.cpu = cpu
        self.cmap = MemoryMap()
        self.mmap = MemoryMap()
        self.bin = p
        self.bin.seek(0)
        self.cmap.write(0, self.bin.read())
        self.cpu.ptr.segment_handler = self.pic_seg_handler

    def read_data(self, vaddr, size):
        return self.mmap.read(vaddr, size)

    def read_instruction(self, vaddr, **kargs):
        maxlen = self.cpu.disassemble.maxlen
        try:
            istr = self.cmap.read(vaddr, maxlen)
        except MemoryError as e:
            logger.warning("vaddr %s is not mapped" % vaddr)
            raise MemoryError(e)
        i = self.cpu.disassemble(istr[0], **kargs)
        if i is None:
            logger.warning("disassemble failed at vaddr %s" % vaddr)
            if len(istr) > 1 and istr[1]._is_def:
                logger.warning("symbol found in instruction buffer" % vaddr)
                raise MemoryError(vaddr)
            return None
        else:
            i.address = vaddr
            return i

    def initenv(self):
        from amoco.cas.mapper import mapper

        m = mapper()
        m[self.cpu.pc] = self.cpu.cst(0, 21)
        return m

    def codehelper(self, **kargs):
        if "seq" in kargs:
            return self.seqhelper(kargs["seq"])
        if "block" in kargs:
            return self.blockhelper(kargs["block"])

    # seqhelper provides arch-dependent information to amoco.main classes
    def seqhelper(self, seq):
        for i in seq:
            # some basic hints:
            if i.mnemonic.startswith("RET"):
                i.misc[tag.FUNC_END] = 1
            elif i.mnemonic == "PUSH":
                i.misc[tag.FUNC_STACK] = 1
            elif i.mnemonic == "POP":
                i.misc[tag.FUNC_UNSTACK] = 1
            # provide hints of absolute location from relative offset:
            elif i.mnemonic in (
                "BC",
                "BNC",
                "BN",
                "BNN",
                "BNOV",
                "BNZ",
                "BOV",
                "BRA",
                "BZ",
                "RCALL",
            ):
                if i.mnemonic == "RCALL":
                    i.misc[tag.FUNC_CALL] = 1
                    i.misc["retto"] = i.address + i.length
                if (i.address is not None) and i.operands[0]._is_cst:
                    offset = i.operands[0].value
                    v = i.address + i.length + (2 * offset)
                    i.misc["to"] = v
                    continue
        return seq

    def blockhelper(self, blk):
        self.seqhelper(blk.instr)
        return blk

    def pic_seg_handler(self, env, seg, base_disp):
        base, disp = base_disp
        if not isinstance(seg, bytes):
            base[8:12] = seg[0:4]
            seg = ""
        return self.cpu.ptr(base, seg, disp)
